

| Subject: | Re: Emmissions problems/exhaust leak |
| From: | Steve Blackham |
| Date: | Wed, 16 May 2001 13:43:28 -0600 |
Mike Mine is doing the same thing. I had some very small exhaust leaks in the connection between the exhaust manifold Y. When I replaced the gaskets and filled the seams with muffler mender, it cut the idle CO in half. Put a rag on the tail pipe and listen for exhaust leaks. Get a spray bottle and fill it with water and dish soap and spray the manifold seams. Look for large growing bubbles not the boiling heat related ones and you see if you have any leaks. I bought a cheap (very cheap, jc whitney) CO meter and have been trying to get the unit into adjustment. Air in the exhuast makes the O2 sensor think its running lean so it richens the mixture. The leaks are small enough so at higher RPM the pressure eliminates air contamination. I'm still not satisfied I'm under the 1.0% CO required here but suspect the head to exhaust gaskets, a new but bad O2 sensor and a ground problem. My O2 sensor voltage bounces around between .45 to .7 with a few .000 and negative spikes. Anyone else have any words of wisdom? Thanks Steve >Date: Wed, 16 May 2001 05:03:48 -0000 >From: Mike Finkbiner <mike_l_f@hotmail.com> >Subject: New Engine, Poor Power, Low Gas Mileage - Update ....... >I had a local shop run the vehicle emissions tests, assuming that if the >fuel pressure regulator were the problem we would see it there. Here's the >results - >RPM Idle 1800 2800 >HC 1398 299 140 >CO 1.51 0.94 0.66 >CO2 8.86 12.7 13.8 >According to the mechanic, that looks pretty good. He doesn't see any need >for adjustments to the AFM idle mixture screw. The one thing he thought was >high was the Idle HC, and a longer duration cam could explain it. >Not sure what to do next. We will probably check the valve adjustments, and >have discussed replacing the Temp II just because it's cheap, but with the >digitool readings looking good, I'm not sure. I sort of hate to just throw >parts at it. Do you suppose the pressure regulator could be a problem, but >it isn't showing up in high CO? >Mike Finkbiner >'87 Westy >Moscow, Idaho -- Steve Blackham Centerville, Utah 77 transporter converted to camper (Westy top) 83 Vanagon (New and current project) 87 Weekender
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